Rapid development and application of base station antenna technologies for mobile communications vigorously promotes a development orientation of a miniaturized, integrated, multifunctional (multiband, multipole, and multipurpose) base station antenna. An antenna feeding network is one of important components of a base station antenna subsystem, and its high performance and miniaturization are important factors that restrict further miniaturization of a base station antenna system. Therefore, designing a high-performance miniaturized base station antenna feeding network has become a focus of antenna technology research.
Currently, there are many documents about base station feeding antenna technologies at home and abroad. The article Impact of a Miniaturized Base Station Antenna publicized on the journal Telecommunications Technology on Dec. 25, 2011 is the most representative. The article mainly describes a tri-band base station antenna that may be applied to 806-960 MHz, 1710-2170 MHz, and 1710-2170 MHz, where a size of the antenna is 1340 mm×380 mm×100 mm.
It can be learned that the base station antenna feeding network in the prior art can cover multiple frequency bands, but the size of the base station antenna feeding network is too large to meet a miniaturization requirement of an antenna in a new communications system.